The turbines used to generate electric power are massive pieces of equipment, however, despite their size, these turbines are made up of a number of intricate parts machined to tight tolerances. The size and complexity of these structures makes an easily described operation such as milling a groove over the circumference of the turbine structure a daunting task. Such a situation occurs in the instance of milling pumping grooves on high pressure cylinder joints. A turbine cylinder is typically joined along a horizontal joint wherein two half sections of the housing together form the outer structure of the turbine. Each housing section has a flat area at which a joint is formed. This is also true of many other structures joined at flanges, such as pumps and other processing equipment, mining equipment and industrial machinery. Such flat areas are exposed both during the initial assembly of the equipment and as a result of rebuild or retrofit operations. In any event, the flat surface or flange surface frequently has features such as grooves or passageways cut into its face, such as the pumping grooves mentioned above, that require precise machining to bring them to within tolerance of their specified dimension.
Whether during initial fabrication or for retrofit or maintenance purposes, such milling typically entails setting up a large scale milling machine weighing over two tons at the site of the turbine. The size of the milling machine results in requiring that a special platform be built to support it and special high duty electrical power sources be connected in order to provide the required power. The above-described operation is thus extraordinantly labor intensive and time consuming. Therefore, it would be desirable to lessen the time required to perform such milling operations, to reduce the manpower required and to reduce the complexity and sheer bulk of the equipment required to mill such grooves within large structures such as steam turbines. Providing such improvements will reduce the cost of such milling operations and increase the speed of the operation, contributing to an overall increase in the productivity of this operation.